1. Field of the Invention
This invention relates to a reproducing apparatus having a plurality of reproducing modes and arranged to discriminate a recording mode on the basis of information reproduced.
2. Description of the Related Art
The known apparatuses of the above-stated kind include magnetic recording/reproducing apparatuses arranged to record with rotary heads one field portion of a video signal in each of recording tracks by obliquely forming these tracks one by one on a magnetic tape and to reproduce the recorded signal with the rotary heads (hereinafter referred to as VTR). The known VTR's include a type wherein the pitch at which the recording tracks are formed (herein after the track pitch will be called TP for short) is determined by selecting one of different speeds at which the tape is moved for recording; and, in carrying out reproduction, the TP is automatically discriminated and reproduction is performed by allowing the tape to travel at the same speed as the speed employed in recording. The VTR of this type is taken up by way of example in the following description of the present specification.
Heretofore, in the VTR of this type, a tracking control signal which is in relation to the recording tracks formed during recording or to the recorded video signals is recorded also during recording along the edge part of the tape in the tape moving direction. During reproduction, the TP, i.e. the tape speed employed in recording, is detected through the recurrent period of the control signal detected by reproduction and the tape moving speed is controlled accordingly for reproduction. However, as a result of a recent tendency to reduce the size of the VTR and to record signals with increased density, it has been proposed to record tracking control pilot signals by superimposing them on the video signals instead of recording the tracking control signal in the above-stated manner. In the VTR of that type, a plurality of different pilot signals are generally superimposed on the recording tracks of the video signals one by one. Then, during reproduction, tracking control is carried out according to a tracking error signal obtained by detecting a difference in level between the pilot signals reproduced from two tracks neighboring on both sides of a recording track being mainly traced for reproduction.
Further, the tracking error signal which is thus obtained is also used for discriminating the TP. In other words, when the tape is allowed to travel for reproduction at a speed different from a travelling speed employed in recording, the tracking error signal is generated at a much greater magnitude than in the case of reproduction at the same tape speed as the speed employed in recording. Therefore, in the event of such a great tracking error signal, the reproducing operation has been carried out by shifting the tape travel speed to an apposite speed. However, in case that a recording operation is performed with the same magnetic head of a VTR, for example, at two different tape travel speeds, one being a fast speed (hereinafter referred to as the SP mode) and the other a slow speed (hereinafter referred to as the LP mode), there obtains a relation of TPs&gt;Hw &gt;TPl, wherein TPs and TPl represent the TP's resulting from recording at these different tape speeds while Hw represents the width of the head. Then, assuming that the recording operation is performed in the manner called overlapping writing at least in the LP mode and that the recording tracks are formed at an effective width TWs in the SP mode and at another effective width TWl in the LP mode, there obtains a relation of TWs&gt;TWl. Therefore, in the event that the information signals recorded in these two modes SP and LP are reproduced in another mode which differs from either of the modes, a maximum output value of the tracking error signal obtainable from each recording track is greater in the case of the SP mode than in the case of the LP mode.
Such being the case, in switching one tape travel speed over to another by checking the tracking error signal for finding out the tape speed employed in recording, the speed switch-over action has been apt to be erroneously performed without adequate consideration of the difference in output value of the tracking error signal due to the above-stated difference in track width. This problem has often hindered apposite reproduction.